The global orientation of today's machine manufacturers having globally residing customers/machine operators raises the need to perform maintenance, error diagnosis and also repair of the machine not only directly on site, but increasingly often via remote access. In this application, the term “machines” includes all machining devices, e.g. for laser machining, for punching or bending, and devices like e.g. laser beam sources, plasma generators or induction generators. The hitherto common direct call of a service computer via an analogue modem or an ISDN connection to a machine is replaced by modern communication techniques, in particular by so-called Virtual Private Networks (abbreviated VPN), allowing an encrypted remote access via the internet. Remote access using VPN has high demands on infrastructure and security. Particularly problematic is the fact that remote access via VPN is dependent on the technology employed by the machine operator. A simple all purpose solution at the machine operator's side is handicapped by the fact that it is hitherto not possible to operate different VPN-software at the same time within one operating system, e.g. at a service computer.
A system and method for remote communication between a central computer and a machine control system are known from the European patent application EP 1 715 395 A1. The known remote communication system 1 shown in FIG. 1 includes a central computer 5 that is protected to the exterior by a firewall 6. At the central computer 5, plural virtual machines 7 are installed that are coexistingly executable and may comprise different operating systems and application programs, in particular tele presence programs and virus protection programs. For each machine control system 3, there is a specifically configured virtual machine 7, by that a communication connection 8 is established from the central computer 5 to the machine control system 3. The service computer 2 is not directly connected with the machine control system 3, but the connection of the service computer 2 is carried out via the central computer 5 that is connected to the service computer 2 via a communication connection 9. All data (dial-in technology, passwords, VPN-software) about the customer and the machine 4 are stored in a database 10 that is connected to the central computer 5. Central computer 5 determines the assigned communication connection 8 as well as the correlated virtual machine 7 by means of the data stored in the database 10, and establishes the communication connection 8 from the virtual machine 7 to the machine control system 3. A communication connection 9 between the service computer 2 and the central computer 5 as well as the communication connection 8 between the central computer 5 and the machine control system 3 are carried out via the internet 11, e.g. via a secured VPN connection.
For remote access to a machine control system 3 of the machine 4, service personnel at first establishes the communication connection 9 between its service computer 2 and the central computer 5. By means of the data stored in the data base 10, the central computer 5 determines the communication connection 8 correlated to the communication control system 3 and selects the executable virtual machine 7 fitted for the machine control system 3 and the communication connection 8 for connecting the machine control system 3 and starts this virtual machine 7. The service personnel executes functions of the machine control system 3 or exchanges data between the machine control system 3 and the central computer 5 via the communication connection 8.
This system is problematic in so far that for specific tasks of the machine maintenance and repair, files have to be transmitted from the machine control system 3. The described system, however, is designed such that file transmission between the machine control system and the service computer is not possible.